Friday, January 27, 2012

One problem with having over 1000 posts is that I can't remember if this is a repost or not. I think this rocket was mentioned previously, either while talking about the never flown 4 O 10,000 to 1 O 10,000 Kosdon project, or perhaps talking about Project Farside. If anyone can remember, post in the comments. Flying such a configuration helps if you want to stick to smaller, more reliable motors rather than giant motors of new design. This comes at the cost of reduced mass fractions and increased drag.

"On 17 October, 2009 a two stage rocket consisting of a cluster of four standard RRS “class” motors in the first stage and a single “class” motor for the second stage (Figure 1) was flown at the Mojave Test Area. Pre-flight modeling suggested a peak altitude of about 45,000 feet and a maximum velocity of about Mach 2.5. Available data indicate that a partial failure of the nose cone attachment resulted in “cocking” of the nose cone and subsequent “coning” of the vehicle as it accelerated. The coning in turn resulted in a trajectory that headed approximately southeastwardly rather than in the planned southwest (downrange) direction. Analysis of video of the second stage burn allows the performance of the rocket to be constrained to a probable burnout velocity above 1700 feet / second at about 6900 feet altitude. Six DOF modeling suggests a maximum altitude of at least 13,000 feet."